Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
doan sai » doan hai, doan mai, doanh tai
thuoc va » thuoc ma, thuong va, thuoc tai
sai cua » dai cua, hai cua, lai cua
thuc va » thuc vat, thuc dan, thuc day
sach ky » sach y, sach ty, sach kem
hieu va » lieu va, hieu qua
nang co » nang cao, nang doc, nang noi
co hoi » co hoc, co loi
sac ky » cac ky, sai ky
va lam » van lam, va lap

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang co hoi. hieu va lam ((thuoc va) OR (thuc va)) doan sai cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang co hoi. hieu va lam ((thuoc va) OR (thuc va)) doan sai cua triet~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang co hoi. hieu va lam ((thuoc va) OR (thuc va)) doan sai cua triet*.